1. Field of the Invention
The invention relates to a series of polyoxyalkylene diamines modified with phenyl groups through ether linkages. The invention also relates to epoxy resin compositions cured with these diamines.
2. Description of the Useful Arts
Epoxy resins constitute a broad class of polymeric materials having a wide range of physical characteristics. The resins are characterized by epoxide groups which are cured by reaction with certain catalysts or curing agents to provide cured epoxy resin compositions with certain desirable properties. One such class of curing agents is, generally, the amines. The most commonly used amine curing agents are aliphatic amines such as diethylenetriamine, triethylenetetramine and the like and/or polyoxyalkylene polyamines; such as polyoxypropylenediamines and triamines and their amino propyl derivatives.
Epoxy resin compositions having improved physical properties are obtained by employing polyoxyalkyleneamines, and polyoxyalkylenediamines in particular, as curing agents.
U.S. Pat. No. 3,222,300 describes polyoxyalkylene glycols modified with glycidyl ethers containing three hydroxyl groups. Those polyhydroxyl components are reacted with polyisocyanate to yield cellular polyurethanes.
U.S. Pat. No. 3,326,895 describes a series of polyoxyalkylene diamines. The diamines are used for curing epoxy resins.
U.S. Pat. No. 3,654,370 describes a process for preparing polyoxyalkylene diamines. These diamines are prepared by the addition of alkylene oxide to an aliphatic polyhydric alcohol. The resulting polyoxyalkylene polyols are reacted with ammonia and hydrogen over a catalyst prepared by the reduction of a mixture of the oxides of nickel, copper and chromium. The diamines are used as curing agents for epoxy resins.